Method and apparatus for heat exchanges



Sept. 13, 1932. s. H. HULSE METHOD AND APPARATUS FOR HEAT EXCHANGES Filed Feb. 6, 1931 ATTORNEYS.

Patented Sept. 13, 1932 UNITED STATES STEWART H.

PATENT oFFicE ETHOD-Ann armm'rns FOB-HEAT nxcnnnens Application filed February-6, 1931. Serial no. 513,873.

gas, by projecting the first liquid against the outside of tubes'through which the second liquid or gas is being circulated. 1 The more turbulent the flow, the more efiicient is the transfer of heat. The preferred equipment for carrying out the invention comprises a centrally. mounted centrifugal device whichcontinuously forces the exterior liquid in all directions over the tube surfaces. The method will be apparent .to those sln'lled in the art to which the invention relates from the following description, taken in connection with the accompanying drawing, wherein Fig. 1 is a view partly in side elevation and partly in section of an apparatus embodying the invention, and i Fig. 2 is a section on line 11-11 of Fig. 1. Fig. 3 is a perspective view of the top and side of agitating device,- showing impeller and deflector blades.

In the drawing, 1 indicates as an entirety a closed tank, which may be of any preferred shape or size and of any desired construction. By preference the tank is elongated and cylin- .drical in shape to avoid the. formation of corners. The tank 1 is formed with an opening 2 in the lower portion, serving as an inlet to the space 4 within the tank. Opening 3 serves as an outlet for the liquid from the body of the tank. Inlet 5 serves as an inlet to the upper part of a header 6, where aliquid to be circulated through thetubes 7 isbrought into the tank. The liquid passing through tubes 7 flows into a second header 8, thence through tubes 9 and leaves the tank by outlet 10 in'the lowerportion of header 6. The above features of a tubular heat exchanger have been used in the past.

In the present invention there is pnovided an agitating device 11, driven from the outside through a shaft 12 which extends through a stuffing box 13. "The agitator consists of an impeller 14 and deflection plates 14a similar to parts of a centrifugal pump. This is accomplished by modifying the usual arrangement of tubes so as to allow for the introduction among the tubes in the exchanger shell of the agitating device, for example, by omitting a portion of the tubes in the upper central part of thetube rest.

Heretofore turbulence in heat exchangers has been produced by a system of bafliing or other means of producing turbulent flow using the velocity of the liquid as it passes through the exchanger. Stirring devices such as revolving .blades have been used'toimpart a circular motion tothe body of the liquid. The use of the-type of agitatingdevice described herein, where the liquid is drawn in through the center of blades and projected HULSE, or ELIZABETH, NEW JERSEY, ASSIGNOB To STANDARD IIOIIILIDE-I VELOPMENT company, A CORPORATION or DELAWARE outwards from the edges with considerable force, has important advantages. The force imparted to the liquid as it leaves the agitating device is so great that the whole body ofthe liquid in the heat exchanger is in such a turbulent state, that all the liquid is in motion,various currents of flow working against each other.

The method of operation is as follows: A

liquid isintroduced into tank 1 continuously by means of inlet 2 and withdrawn by outlet 3.

A second liquid of different temperature is continuously circulated through inlet 5, the upper portion of. header 6, tubes 7, header 8, tubes 9, the lower portion-of header. 6, and outlet 10. The agitating device being operated at the same time produces turbulence of the first liquid, in contact with the tubescon-' 'taining the second liquid and causes a more efficient transfer of heat than'is found in heat exchangers not so equipped. Liquids containing sediment in flowing throughthe usual type of exchangers are inclined to deposit this'material upon the tube surfaces, but by agitating the liquid this is avoided so the sediment is not allowed to settle and is kept in suspension and removed from the exchanger with the liquid.

The introduction of the agitating device into a heat exchangernsed' intransference of heat of two liquids such asoil, shows the following improvements of heat transfer under similar conditions, such as rate of pumping and quantity of oil:

loo

The oils without the agitating device had temperatures changed from 700 F. to 400 F. and 200 F. to 300 F. With the agitating device, although a portion of the tubes was removed, the temperatures changed from 7 00 F. to 345 F. and from 200 F. to 31 8'F. The power requirements in producing turbulence in the heat exchanger by means of an' injector of the type described are relatively 10 low when compared with power used in operating pumps to produce high liquid velocity to produce same heat transfer. The efiiciency of the heat exchanger equipped with the ejector is increased with an increase of only 15, approximately one-quarter of the amount of additional power requirements as would ,be required to similarly increase the efficiency of the heat exchanger by increasing the Velocity of the liquid flowing through the exchanger.

Various changes and alternative'arrangements may be made within the scope of the appended claims in which it is my intention to claim all novelty inherent in the invention" as broadly as the prior art permits.

I claim: 7

1. In heat exchange apparatus, a tank for holding a body of liquid, means for convey- 1 ing liquid into the tank, means for conveying liquid out of the tank, pipes through which a liquidof different temperature flows and arranged to be immersed in the body of liquid, connections-with said pipes for supplying the liquid thereto and conveying it therefrom, and a means within the tank for ejecting the liquid from a common center radially outwardly in all directions thereby efiecting turbulent circulation of the liquid uniformly throughout the tank.

2. In heat exchange apparatus, a tank for 40 holding a body of liquid, connections for supplying the liquid thereto and conveying it therefrom, spaced series of pipes through:

, which a temperature changing liquid flows,

and arranged to be immersed in the body of the liquid, connections with each series of pipes for supplying the liquid thereto and conveying it therefrom, means within the tank for ejecting the liquid from a common center radially outwardly in all directions thereby effecting turbulent circulation of the liquid uniformly throughout the tank.

3. Apparatus according to claim 2, ,in' which the ejecting means consists of animpeller and deflection plates similar to parts of a centrifugal pump.

4. The method of efl'ecting heat exchange," comprising flowing a liquid about the exte-, rior of tubes, and simultaneously ejecting a portion of the liquid from a common center Y radially outwardly in all directions thereby effecting turbulent circulation of the liquid.

"STEWART H. HULSE. 

